International Standard (TSO 7627/ 4 Hardmetals - Chemical analysis by. flame:atomic absorption .spectrometry Part 4: Determination of molybdenum, titanium and vanadium in contents from 0,01 to 0,5 % (m/m) Metaux-durs -- 'Analyse chimique par spectrometrie d'absorption atomique dans la flamme'-- Partie 4: Dosage du molybdene, du titane et du vanadium a des teneurs comprises entre 0,01 et 0,5 % (m/m) First edition - 1983-10-15 Foreword ISo (the International Organization for Standardization)is a worldwidefederation of national standards bodies (Iso member bodies). The work of developing International interested in a subject for which a technical committee has been authorized has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with Iso, also take part in the work. Draft International Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as International Standards by theIsoCouncil. International Standard ISo 7627/4 was developed by Technical Committee ISO/TC119, Powder metallurgy, and was circulated to the member bodies in August 1982. It has been approved by the member bodies of the following countries : Austria Germany,F.R Spain Brazil Italy Sweden Bulgaria Korea, Rep. of Switzerland China Norway United Kingdom Czechoslovakia Poland USA Egypt, Arab Rep. of Romania USSR France South Africa, Rep. of No member body expressed disapproval of the document. @ International Organization for Standardization, 1983 Printed in Switzerland INTERNATIONAL STANDARD ISO 7627/4-1983 (E) Hardmetals --. Chemical analysis by flame atomic absorption spectrometry Part 4: Determination of molybdenum, titanium and vanadium in contents from 0,01 to 0,5 % (m/m) 1 Scope and field of application 4.2 Dissolution of the test portion This part of ISo 7627 specifies the method to be used for the Add 10 ml of water, 5 ml of the hydrofluoric acid (3.1). and determination of molybdenum, titanium and vanadium con. then 5 ml of the nitric acid (3.2), drop by drop, to the beaker tents of hardmetals within the range 0,01 to 0,5 % (m/ m) by containing thetest portion (4.1)and heat gentlyuntil thetest flame atomic absorption spectrometry. portion is completely dissolved. Add 10 ml of the caesium chloride solution (3.4) and 10 ml of the ammonium fluoride General requirements concerning the fielid of application, prin- solution(3.3).Then transfer thesolution totallyto a 100 ml ciple, interfering elements, apparatus, sampling and test report polypropylene one-mark volumetric flask and dilute to the aregiveninISO7627/1. mark. Reference 4.3 Dilution volume ISO 7627/1, Hardmetals -- Chemical analysis by flame atomic Prepare the relevant dilution volume for the analysis according absorption spectrometry - Part 1: General requirements. totable1asfollows: Reagents 4.3.1Dilutionvolume100ml:usethesolutionin4.2. 3.1 Hydrofluoric acid, Q 1,12 g/ml. 4.3.2 The.concentration of the solution may be reduced by a factor of 10 for instruments of higher sensitivity by transferring 10 ml of the solution in 4.2 to a 100 ml polypropylene one-mark 3.2 Nitric acid, @ 1,42 g/ml. volumetric flask.Add 10ml of the caesium chloride solution (3.4). Add 10 ml of the ammonium fluoride solution (3.3) and 3.3 Ammonium fluoride, O,1 g/ml solution. dilute to the mark. 3.4 Caesium chloride, 0,01 g/ml solution. 4.4 Preparation of calibration and blank solutions 3.5 High-purity stock solutions, for calibration purposes for eachelementtobedetermined,containing1,o00gof the 4.4.1 Prepare at least six solutions according to 4.2 with a element per litre. matrix composition as similar as possible to the test portion to be analysed, but without making up to volume. Then add in- NOTE Thisvalue is understood to establish a maximum limit of creasing volumes of properly diluted stock solutions of the 1,000 5 g and a minimum limit of 0,999 5 g. elementstobe determined according to the